package org.cosmocalc;

public class Drdzprop implements MathFunction {

	private Cosmology cosmology;
	
	public Drdzprop(Cosmology cosmology){
		this.cosmology = cosmology;
	}
	public double f(double z) {
		return ((cosmology.getC_H() / Math.sqrt(Math.pow((1 + z), 2.)
				* (cosmology.getOmegaM() * z + 1) - cosmology.getOmegaL() * z
				* (z + 2))) / (1. + z));
	}
}
